In First Day of Trading, Shares
Of Healtheon Nearly Quadruple

SANTA CLARA, Calif. -- Shares of Healtheon Corp. nearly quadrupled in their first day of trading, as the medical-data company became the latest sensation among investors looking for an Internet play.

On Wednesday evening, Healtheon priced its initial public offering at $8 a share. The stock opened trading Thursday at $21.75 a share and surged throughout the day on hectic volume of nearly six million shares. It finished at $31.375 in...